Ok - the problem seems to be that I have 2 monitors. I'm in Ubuntu 2D. The top bar on the left primary monitor when maximised Sublime shows the Menu (File, Edit etc) but on the secondary monitor I lose this, and with it the ability to restore the size or move it. It's a real pain in the arse because the menu will not show unless the window is maximised for me.

Perhaps there needs to be an option to bring up the menu bar on a restored window - unless it's just me having borked my system in some way which is entirely possible - it doesn't show by default for me.